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Finding the Fourth Proportional to 805.85, 1,208.95 and 285.88

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Solution

The fourth proportional to 805.85, 1,208.95 and 285.88 is: 428.88

Step by Step Solution

  1. Step 1: Write the proportion equation
    805.85 : 1,208.95 = 285.88 : x
  2. Step 2: Convert to fraction form
    805.85/1,208.95 = 285.88/x
  3. Step 3: Cross multiply
    805.85x = 1,208.95 × 285.88
  4. Step 4: Simplify right side
    805.85x = 345,613.96
  5. Step 5: Solve for x
    x = 345,613.96/805.85
  6. Step 6: Final answer
    x = 428.88

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Why These Related Problems?

These problems maintain the same ratio (1.50) or explore similar proportional relationships. Practicing with related ratios helps build understanding of proportional relationships.